USING PULSE-SHAPE DISCRIMINATION TO SORT INDIVIDUAL ENERGY DEPOSITIONEVENTS IN A GERMANIUM CRYSTAL

A fast digital oscilloscope based pulse shape discrimination (PSD) sys tem has been tested with intrinsic germanium detectors large enough to allow ionizing events which generate localized electron-hole pairs at a single site to be segregated from those depositing energy at severa l different sites in the crystal. Drift velocities of the electrons an d holes result in pulses several hundred nanoseconds long. Since the e lectric field varies by almost a factor of 10 between the outer and in ner surfaces, collection of electrons and holes can frequently be dist inguished, and pulses due to multi-site events can be distinguished fr om single site events.